Interaction of atherosclerosis and inflammation in elderly subjects with poor cognitive function

OBJECTIVE: To test the hypothesis that a pro-inflammatory response is associated with cognitive impairment among individuals with cardiovascular disease. METHOD: All 85-year-old inhabitants of Leiden (n = 599) were visited at their place of residence. A history of cardiovascular disease and an EKG were used as indicators of atherosclerosis. Production of the pro-inflammatory cytokine tumor necrosis factor-alpha and the anti-inflammatory cytokine interleukin-10 was assessed in a whole-blood assay using lipopolysaccharide as a stimulus. Global cognitive functioning was determined with the Mini-Mental State Examination (MMSE); attention, cognitive speed, and memory were determined with four neuropsychological tests; and a history of dementia was obtained. RESULTS: In subjects with cardiovascular disease, median MMSE scores were lower in those with a pro-inflammatory response when compared with those with an anti-inflammatory response (p = 0.02). Similar associations were found for the Stroop Test, measuring attention (p < 0.01), the Coding Test measuring cognitive speed (p = 0.02), the Word Learning Test measuring memory (p < 0.01), and the presence of dementia (p = 0.04). The associations remained unaltered after adjustments for possible confounders such as gender, level of education, use of nonsteroidal anti-inflammatory drugs, use of cardiovascular drugs, and cardiovascular risk factors. In contrast, outcomes of the cognitive tests and presence of dementia were not dependent on the inflammatory response when cardiovascular disease was absent. CONCLUSION: The combination of cardiovascular disease and a pro-inflammatory cytokine response may be associated with cognitive impairment and dementia.